BIVBlog #50: Floating Microcontroller Inputs, Single Throw Switches and Pull-Up/Pull-Down Resistors

Feeding analog voltages to digital microcontroller inputs already got us some interesting effects, but what about leaving an input pin entirely disconnected? All of a sudden microcontrollers become sensitive to the weather outside, and the clothes we wear—or any other source of electrostatic.

The easy way to deal with this is to always ensure that an input is always fed a proper input voltage. But if we want to use a “single throw” (or “connect—disconnect”) type of switch or pushbutton, then we have to use a simple, high value resistor as a “pull-up” or “pull-down” resistor.

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BIVBlog #42: Leaving the Pre-built Microcontroller Target Boards Behind

As useful as the various pre-made evaluation target boards were to get our microcontroller development toolchain up and running, they are starting to become a burden. Dropping them now, and dealing with everything they have taken care of for ourselves so far, makes a lot of sense in the long run: It gives us more options with regard to microcontroller models and peripherals we can connect. Aside from that, bare components and a breadboard are usually cheaper than the equivalent evaluation board, so this may even save us a couple bucks.

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